Calutrons



Sept. 2, 1958 J. THORNTON CALUTRONS Filed Oct. 11, 1945 FIE EL INVENTOR. Jer/5 7/7 0/v7 fof-7 ATTORNEY.

@hired CALUTRONS Jens Thornton, Quincy, Mass., assignor, bymesne assignments, to the United States of America as represented by the United States Atomic Energy Commission Application ctoher 11, 1945, Serial No. 621,850

6 Claims. (Cl. Z50-41.9)

The present invention relates to calutrons and more particularly to calutrons of the character disclosed in the United States Patents to Ernest O. Lawrence, No. 2,709,222, issued May 24, 1955, and No. 2,714,644, issued August 2, 1955.

At the outset it is noted that a calutron is a machine of the character of that disclosed in the above-mentioned Lawrence patents, and is employed to separate the constituent isotopes of an element and more particularly to increase the proportion of a selected isotope in an element containing several isotopes in order to produce the element enriched with the selected isotope. For example, the machine is especially useful in producing uranium er1- riched with U235.

Such a calutron essentially comprises means for vaporizing a quantity of material containing an element that is to be enriched with a selected one of its several isotopes; means for subjecting the vapor to ionization, whereby at least a portion of the vapor is ionized causing ions of the several isotopes of the element to be produced; electrical means for segregating the ions from the uri-ionized vapor and for accelerating the segregated ions to relatively high velocities; electromagnetic means for deecting the ions along curved paths, the radii of curvature of the paths of the ions being proportional to the square roots of the masses of the ions, whereby the ions are concentrated in accordance with their masses; and means for de-ionizing and' collecting the ions of the selected isotope thus concentrated, thereby to produce a deposit of the element enriched with the selected isotope.

it is an object of the present invention to increase the eiiciency ot a calutron arrangement by employing supporting structure for the calutron tanks as a return yoke for magnetic ux.

it is a further object of the present invention to provide a caiutron including magnetic means in which mechanical support for the calutron tank is provided by the magnet.

it is a further object of the present invention to provide a calutron arrangement comprising an alternated series of tanks and magnets in combination with a magnetic yoke arranged to support the tanks and electromagnets.

Other objects not enumerated above will become apparent as the description proceeds, especially when taken in conjunction with the appended drawings in which Figure l is a side elevation of the described calutron arrangement and Fig. 2 is a section on the line 2 2 of Fig. 1.

Referring now to the drawings, the calutron arrangement illustrated comprises a series of tanks 10 each of which contains ion separating mechanism. The tanks are conventionally formed of steel and are made to withstand atmospheric pressure when evacuated to pressure on the order of 104 or 10-5 mm. Hg. in order to evacuate the tanks l each is connected at its side to a laterally extending vacuum manifold 11 which in turn is connected to a plurality of diffusion pumps 2,850,637 Patented Sept. 2, 1958 rice 12. The specic details of the evacuating mechanism forms no part of the present invention and it is suiicient to state that evacuation is carried out by a plurality of diiusion pumps in conjunction with a plurality of mechanical backing pumps.

The ion separating mechanism comprises a plurality of ion transmitters 13 and a plurality of receivers 14. It wiil be noted 'that in the present illustrated embodiment it is contemplated that a substantial number of transmitters will be placed side by side, transmitting beams to a corresponding plurality of ion receivers. Since the operation of ion separating mechanism of this type is fully disclosed in the patents identiiied above, no elaboration of the same will be made herein.

In the illustrated embodiment, tank 10 is of substantial length and has its lower corners truncated as indicated at 15. This truncation of the tank conserves space and it will be observed that the walls of the tank 19 are thus caused to lie closely adjacent to the outermost ion beams. The top wall 16 of the tank itl is removably secured to the tank and will be provided with conventional sealing means (not shown). It will be observed that the several transmitters 13 and receivers 14 are supported directly by the removable top wall 16 and this permits removal of the top wall and the complete ion separating mechanisin by simply elevating the top wall 16, which may be done by a conventional overhead hoist.

1 have illustrated a series of tive tanks 10 which are spaced apart in a horizontal straight line, although it will be appreciated that the number of tanks thus provided may vary widely.

Magnetic structure is provided for establishing a substantially uniform magnetic held through each of the tanks 10 and this structure comprises a plurality of electromagnets 2t), there being an electromagnet positioned closely adjacent each side of each or" the tanks. This arrangement provides a magnet between the individual tanks of an adjacent pair as well as an outer electromagnet at each end of the series. in other words, the arrangement comprises a series of alternated tanks and magnets, the end elements of the series being electromagnets.

The electromagnets each comprises a winding 20A shaped to conform substantially to the transverse shape of the tank and having an inner opening substantially conforming to the transverse cross section of the tank. These windings are connected in such a direction that each tends to set up a magnetic eld extending in the same direction through the series of tanks and magnets. Inside the windings there are provided core members ZtB whose cross sectional shape and area conform substantially to the cross sectional shape and area of the tanks 16.

Adjacent to and preferably contacting the end electromagnet 2i) l have provided vertical yoke portions 22 which extend downwardly substantially to the plane containing the undersides of the electromagnets Ztl. i have further provided a horizontally extending yoke portion 23 which is in good ilux conducting relationship to the vertical yoke portions 22 and whose upper surface lies substantially in the plane of the under surfaces of the electromagnets 20.

The yoke portion 23 may thus Ibe employed as a mechanical support both for the tanks 10 and the electromagnets 20. As illustrated in Fig. 1 the electromagnets 2h may rest directly upon the upper surface of the yoke portion 23. I have illustrated the tanks 1t?, however, `as resting upon separate supports 24 which in turn rest upon the upper surface of the yoke portion 23. The supports 24 may conveniently take the form of concrete blocks or the like. While the detailed structure of the yoke portion 23 is not illustrated, it will be appreciated that the essentialY consideration is that it shall contain suicient material of a high magnetic permeability to provide a satisfactory path for the magnetic ux set up Iby the electromagnets 2(1). Thus in practice the yokeportion 23 mayV be essentiallya foundation element containing suicient Vstructural steel elements to carry the magnetic flux with- V ciated that the saving in iron effected by combining the function of a structural support and a return yoke in a single element is very material. Furthermore, the disclosed arrangement has the advantage that the return yoke is thus located ina position where it causes a minimum of interferencewith the calutron tank and specifically permits access to both the top and side walls thereof.

While I have illustrated a tank of a particular shape and further illustrated the ion separating mechanism as supported from a removable top closure plate it will be appreciated that the shape of the tank is of no particular significance in the present invention and that instead of the shape shown, the tank could well be rectangular, U- shaped, or circular as desired. It will further be appreciated that the ion separating mechanism disclosed is Y merely illustrative of the type of mechanism to be employed in the tank and that the precise structure and arrangement of the elements that make up this mechanism may be varied as desired. More generally, while I have illustrated a single preferred embodiment of my improved Vcalutron arrangement it will be appreciated that this has been done merely to enable those skilled in the art to practice the invention the scope of which is indi cated by the appended claims. Y

mon center line, ion separating mechanism disposed ink each of said tanks, a longitudinal member of ferromagnetic material disposed parallel to said center line for supporting said tanks, end members of ferromagnetic material magnetically joined to said longitudinal member at the ends thereof and vperpendicular thereto, an electromagnet disposed between adjacent tanks and between end tanks and end members, each electromagnet comprising a winding substantially conformed to the perimeter of said tanks and surrounding a ferromagnetic core having substantially the'sameconguration as the parallel faces of said tanks, and electrical means connected to said windings for establishing magnetic fields through each of said tanks in the same direction with said end and longitudinal members. providing a magnetic flux return path. Y

3'. A calutron arrangement comprising a` plurality of evacuated tanks, a plurality of electromagnets, each of said electromagnets comprising an electrical Winding disposed aboutthe perimeter of a ferromagnetic core having substantially the same configuration as said tanks, said tanks and said electromagnets being disposed alternately in a linear array having a common center line, the end elements of said linear array being electromagnetsa ferromagnetic structure having endmembers contiguous with the end elements of said linear array and an elongated member magnetically interconnecting said end members, and electrical means connected to said windings for establishing a magnetic flux through said linear array parallel to thercenter linethereof.

4. A calutron arrangement comprising a plurality of evacuated tanks, a plurality of electromagnets, each of said electromagnets comprising an electrical winding disposed about the perimeter of a ferromagnetic core having substantially the same contiguraton as said tanks, said tanks and said electromagnets Vbeing, alternately disposed in a linear array having a common center line, the end elements of said linear array being electromagnets, electrical means connected to said windings for establishing a magnetic flux through said linear array Yparallel-to the center line thereof, .and magnetic yoke structure disposed about three sides of said linear array and having end memberscontiguous with the end elements of saidlinear array and an elongated member abutting said end members for supporting the elements of said linear array and providing a return path for said magnetic flux.

5. A calutron arrangement comprising a plurality of substantially fluid-tight tanks, means for evacuating said tanks, a plurality 'of electromagnets,V each of saidelectromagnets comprising an electrical Winding disposed about the perimeter of a` magnetic core having substantially the same configuration as said tanks, said tanksl and said electromagnets being alternately Vdisposed in a linear array having a common center line, the end elements of said linear array being electromagnets, electrical means connected tosaid windings for establishing a magnetic flux through said linear array parallel to the center line thereof, a magnetic structure having end members contiguous with-the end elements of said linear array and an elongated member magnetically interconnecting said end members, a plurality of transmitters respectively disposed in said'tanks and arranged to transmit a plurality of ion beams therein transversely through said magnetic ux, and-a plurality of receivers respectively .disposed in Y said tanks to receive and collect desired portions of said ion beams. n

6, A calutron arrangement comprising a plurality of substantially duid-tight tanks disposed parallel to one another and spaced-apart in an aligned array along a cornmon center line, ion separating mechanism disposed'in each of said tanks, a longitudinal member of ferromagneticV material disposed adjacent said tank array and parallel Vto saidycenter line, end members of Vferromagneticmaterial magnetically joined to the outer ends of said longitudinal member and extended parallel to the endvtanks'of said array, a plurality of electromagnets, said electromagnets being disposed one between successive pairs of tanks and between'each end member andad- 'jacent'tanlg eachgof said electromagnets comprising at least a winding having substantially the same configuration as the parallel faces of said tanks, and electrical means connected to said windings for establishingvmagnetic'iields through each of said tanks in the same direction parallel to the common center line thereof withV said end and longitudinal members providing a magnetic flux return path.

ReferencesrCited in the-file of this patent UNITED STATES PATENTS OTHER REFERENCES Nien-Review of Scientific Instruments, vol. 11, July,V

1940, pp. l212-216.

VCoggeshall et al.-Review of Scientific Instruments,

vol. 14, May, 1943, pp. .12S-.129. 

